Same Tree is an example of tree problems. In this post we will write a function to check if they are equal or not in Javascript.

Problem Description

Given two binary trees, write a function to check if they are equal or not. Two binary trees are considered equal if they are structurally identical and the nodes have the same value.

Nothing fancy, just perform a preorder traversal for both trees at the same pace, simply return false whenever we found a mismatch, otherwise continue the traversal on both left and right subtrees.

Time complexity: O(n)

Space complexity: O(1) (ignore recursion stack, otherwise the height of the tree)

Solution: Please check the main.js snippet for the solution. If you have different approach in mind or have any suggestion for this implementation feel free to share in the comment below. Thanks!